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MG MG Y Type - COIL TESTING DATA
|I have tested the coil off a YA or YB with an ohmeter with the result as far as I can make out that the primary circuit is about 3.5 ohms and the secondary (HT) circuit measures about 5000 ohms. |
Does anyone know if these results are correct for the Y-Type coils or is it likely to be scrap? I understand that the readings for a modern car arew likely to be much higher, but does this apply to those designed 60 odd years ago?
I would appreciate any ideas on this because I intend to put it on E-Bay shortly if it is O.K.
I just tested the "old faithful" that is on my engine test rig and that had Primary circuit of 4.7 ohm and Secondary circuit of 5370 ohm.
I am a little skeptical about the 4.7 ohm reading as I know most modern coils run either 3.5 or 1.5 ohm (the latter usually having an external ballast resistor) so I would say yours is in the ball park.
Sorry for any delay in getting back to you.
|Many thanks Paul|
I wasn't at all sure but your reply gives me a great deal more confidence. I had googled "how to test a coil" and the figures given for modern coils indicate a much higher secondary coil resistance and as you say a lower resistance for those with a ballast resistance. There are a few articles on this subject, most of which go over my head!
Your help is much appreciated
|You are welcome Clive. Your coil will work OK with T Types and also witht he Wolsely 4/44 and indeed many cars of the same period using the XPAG so do not limit your appeal tojust the MG Y Type in your eBay description.|
A good coil will promote good starting performance and avoid the sort of poor starting that plaqued cars in the 1960s. Of course a good battery, good grounding and clean terminals all help too. Amazingly of all my cars though, stored in exactly the same garage, the Y is the easiest to start after prolonged idleness - such great cars.
|Thanks again Paul. I have been wondering why the design for modern coils differs so much in specification so much from classsic ones. The only thoughts that I can come up with was that perhaps there was a shortage of copper in the mid 1940s or maybe todays higher compression engines need more of s spark, hence the higher voltage?|
How is the T-Type getting on by the way?
|Sorry Paul, I meant the YT of course. Penalty of advancing years!|
This thread was discussed between 28/09/2010 and 04/10/2010
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